Contents

The title refers to the distance traveled while under the sea and not to a depth, as 20,000 leagues (80,000 km) is nearly twice the circumference of the Earth.[6] The greatest depth mentioned in the book is four leagues. The book uses metric leagues, which are four kilometres each.[7]

During the year 1866, ships of several nations spot a mysterious sea monster, which some suggest to be a giant narwhal. The United States government assembles an expedition in New York City to find and destroy the monster. Professor Pierre Aronnax, a French marine biologist and narrator of the story, who happens to be in New York at the time, receives a last-minute invitation to join the expedition, which he accepts. Canadian whaler and master harpoonist Ned Land and Aronnax's faithful servant Conseil are also brought aboard.

The expedition departs 34th Street Pier in Manhattan aboard the United States Navy frigate Abraham Lincoln and travels south around Cape Horn into the Pacific Ocean. After a long search, the ship finds the monster and then attacks the beast, which damages the ship's rudder. The three protagonists are then hurled into the water and grasp hold of the "hide" of the creature, which they find, to their surprise, to be a submarine very far ahead of its era. They are quickly captured and brought inside the vessel, where they meet its enigmatic creator and commander, Captain Nemo.

The rest of the story follows the adventures of the protagonists aboard the creature—the submarine, the Nautilus—which was built in secrecy and now roams the seas free from any land-based government. Captain Nemo's motivation is implied to be both a scientific thirst for knowledge and a desire for revenge upon (and self-imposed exile from) civilization. Nemo explains that his submarine is electrically powered and can perform advanced marine biology research; he also tells his new passengers that although he appreciates conversing with such an expert as Aronnax, maintaining the secrecy of his existence requires never letting them leave. Aronnax and Conseil are enthralled by the undersea adventures, but Ned Land can only think of escape.

They visit many places under the ocean, some real-world and others fictional. The travelers witness the real corals of the Red Sea, the wrecks of the battle of Vigo Bay, the Antarctic ice shelves, the Transatlantic telegraph cable and the legendary submerged land of Atlantis. The travelers also use diving suits to hunt sharks and other marine life with air-guns and have an underwater funeral for a crew member who died when an accident occurred under mysterious conditions inside the Nautilus. When the Nautilus returns to the Atlantic Ocean, a pack of "poulpes" (usually translated as a giant squid, although in French "poulpe" means "octopus") attacks the vessel and kills a crew member.

Throughout the story Captain Nemo is suggested to have exiled himself from the world after an encounter with the forces that occupied his country that had devastating effects on his family. Not long after the incident of the poulpes, Nemo suddenly changes his behavior toward Aronnax, avoiding him. Aronnax no longer feels the same and begins to sympathize with Ned Land. Near the end of the book, the Nautilus is attacked by a warship of some nation that had made Nemo suffer. Filled with hatred and revenge, Nemo ignores Aronnax's pleas for mercy. Nemo—nicknamed "angel of hatred" by Aronnax—destroys the ship, ramming it just below the waterline, and consequently sinking it into the bottom of the sea, much to Aronnax's horror, as he watches the ship plunge into the abyss. Nemo bows before the pictures of his wife and children and is plunged into deep depression after this encounter. For several days after this, the protagonists' situation changes. No one seems to be on board any longer and the Nautilus moves about randomly. Ned Land is even more depressed, Conseil fears for Ned's life, and Aronnax, horrified at what Nemo had done to the ship, can no longer stand the situation either. One evening, Ned Land announces an opportunity to escape. Although Aronnax wants to leave Nemo, whom he now holds in horror, he still wishes to see him for the last time. But he knows that Nemo would never let him escape, so he has to avoid meeting him. Before the escape, however, he sees him one last time (although secretly), and hears him say "Almighty God! Enough! Enough!". Aronnax immediately goes to his companions and they are ready to escape. But while they loosen the dinghy, they discover that the Nautilus has wandered into the Moskenstraumen, more commonly known as the "Maelstrom". They manage to escape and find refuge on a nearby island off the coast of Norway, but the fate of the Nautilus is unknown.

Captain Nemo's name is an allusion to Homer's Odyssey, a Greek epic poem.[citation needed] In The Odyssey, Odysseus meets the monstrous cyclopsPolyphemus during the course of his wanderings. Polyphemus asks Odysseus his name, and Odysseus replies that his name is "Utis" (ουτις), which translates as "No-man" or "No-body". In the Latin translation of the Odyssey, this pseudonym is rendered as "Nemo", which in Latin also translates as "No-man" or "No-body". Similarly to Nemo, Odysseus must wander the seas in exile (though only for 10 years) and is tormented by the deaths of his ship's crew.

Jules Verne several times mentions Commander Matthew Fontaine Maury, "Captain Maury" in Verne's book, a real-life oceanographer who explored the winds, seas, currents, and collected samples of the bottom of the seas and charted all oceans. Verne would have known of Matthew Maury's international fame and perhaps Maury's French ancestry.

References are made to other such Frenchmen as Jean-François de Galaup, comte de Lapérouse, a famous explorer who was lost while circumnavigating the globe; Dumont D'Urville, the explorer who found the remains of Lapérouse's ship; and Ferdinand Lesseps, builder of the Suez Canal and the nephew of the sole survivor of Lapérouse's expedition. The Nautilus seems to follow the footsteps of these men: she visits the waters where Lapérouse was lost; she sails to Antarctic waters and becomes stranded there, just like D'Urville's ship, the Astrolabe; and she passes through an underwater tunnel from the Red Sea into the Mediterranean.

The most famous part of the novel, the battle against a school of giant squid, begins when a crewman opens the hatch of the boat and gets caught by one of the monsters. As the tentacle that has grabbed him pulls him away, he yells "Help!" in French. At the beginning of the next chapter, concerning the battle, Aronnax states, "To convey such sights, one would take the pen of our most famous poet, Victor Hugo, author of The Toilers of the Sea." The Toilers of the Sea also contains an episode where a worker fights a giant octopus, wherein the octopus symbolizes the Industrial Revolution. It is probable that Verne borrowed the symbol, but used it to allude to the Revolutions of 1848 as well, in that the first man to stand against the "monster" and the first to be defeated by it is a Frenchman.[citation needed]

In several parts of the book, Captain Nemo is depicted as a champion of the world's underdogs and downtrodden. In one passage, Captain Nemo is mentioned as providing some help to Greeks rebelling against Ottoman rule during the Cretan Revolt of 1866–1869, proving to Arronax that he had not completely severed all relations with mankind outside the Nautilus after all. In another passage, Nemo takes pity on a poor Indian pearl diver who must do his diving without the sophisticated diving suit available to the submarine's crew, and who is doomed to die young due to the cumulative effect of diving on his lungs. Nemo approaches him underwater and gives him a whole pouch full of pearls, more than he could have acquired in years of his dangerous work. Nemo remarks that the diver as an inhabitant of British Colonial India, "is an inhabitant of an oppressed country".

The breathing apparatus used by Nautilus divers is depicted as an untethered version of underwater breathing apparatus designed by Benoit Rouquayrol and Auguste Denayrouze in 1865. They designed a diving set with a backpack spherical air tank that supplied air through the first known demand regulator.[9][10][11] The diver still walked on the seabed and did not swim. This set was called an aérophore (Greek for "air-carrier"). Air pressure tanks made with the technology of the time could only hold 30 atmospheres, and the diver had to be surface supplied; the tank was for bailout.[9] The durations of 6 to 8 hours on a tankful without external supply recorded for the Rouquayrol set in the book are greatly exaggerated.[10]

No less significant, though more rarely commented on, is the very bold political vision, which was revolutionary for its time, represented by the character of Captain Nemo. As revealed in the later Verne book The Mysterious Island, Captain Nemo is a descendant of Tipu Sultan, a Muslim ruler of Mysore who resisted the expansionism of the British East India Company. Nemo took to the underwater life after the suppression of the Indian Mutiny of 1857, in which his close family members were killed by the British. This change was made at the request of Verne's publisher, Pierre-Jules Hetzel, who is known to be responsible for many serious changes in Verne's books. In the original text the mysterious captain was a Polish nobleman, avenging his family who were killed by the Russians in retaliation for the captain's taking part in the Polish January Uprising of 1863. As France was at the time allied with the Russian Empire, the target for Nemo's wrath was changed to France's old enemy, the British Empire, to avoid political trouble. Professor Pierre Aronnax does not suspect Nemo's origins, as these were explained only later, in Verne's next book. What remained in the book from the initial concept is a portrait of Tadeusz Kościuszko, a Polish national hero, leader of the uprising against Russia in 1794, with an inscription in Latin: "Finis Poloniae!" ("The end of Poland!").

Theodore L. Thomas in 1961 said that "there is not a single bit of valid speculation" in the novel and that "none of its predictions has come true". He described the depictions of the diving gear, scenes, and the Nautilus as "pretty bad, behind the times even for 1869 ... In none of these technical situation did Verne take advantage of knowledge readily available to him at the time". Thomas said, however, that despite poor science, plot, and characterization, "Put them all together with the magic of Verne's story-telling ability, and something flames up. A story emerges that sweeps incredulity before it".[10]

Jules Verne's wrote a sequel to this book: L'Île mystérieuse (The Mysterious Island, 1874), which concludes the stories begun by Twenty Thousand Leagues Under the Sea and In Search of the Castaways. While The Mysterious Island seems to give more information about Nemo (or Prince Dakkar), it is muddied by the presence of several irreconcilable chronological contradictions between the two books and even within The Mysterious Island.

Verne returned to the theme of an outlaw submarine captain in his much later Facing the Flag. That book's main villain, Ker Karraje, is a completely unscrupulous pirate acting purely and simply for gain, completely devoid of all the saving graces which gave Nemo—for all that he, too, was capable of ruthless killings—some nobility of character.

Like Nemo, Ker Karraje plays "host" to unwilling French guests—but unlike Nemo, who manages to elude all pursuers, Karraje's career of outlawry is decisively ended by the combination of an international task force and the rebellion of his French captives. Though also widely published and translated, it never attained the lasting popularity of Twenty Thousand Leagues.

More similar to the original Nemo, though with a less finely worked-out character, is Robur in Robur the Conqueror—a dark and flamboyant outlaw rebel using an aircraft instead of a submarine—and its sequel Master of the World.

The novel was first translated into English in 1873 by Reverend Lewis Page Mercier. Mercier cut nearly a quarter of Verne's original text and made hundreds of translation errors, sometimes dramatically changing the meaning of Verne's original intent (including uniformly mistranslating French scaphandre — properly "diving apparatus" — as "cork-jacket", following a long-obsolete meaning as "a type of lifejacket"). Some of these mistranslations have been done for political reasons, such as Nemo's identity and the nationality of the two warships he sinks, or the portraits of freedom fighters on the wall of his cabin which originally included Daniel O'Connell.[13] Nonetheless, it became the standard English translation for more than a hundred years, while other translations continued to draw from it and its mistakes (especially the mistranslation of the title; the French title actually means Twenty Thousand Leagues Under the Seas).

In the Argyle Press/Hurst and Company 1892 Arlington Edition, the translation and editing mistakes attributed to Mercier are missing. Scaphandre is correctly translated as "diving apparatus" and not as "cork-jackets". Although the book cover gives the title as Twenty Thousand Leagues Under the Sea, the title page titles the book Twenty Thousand Leagues Under the Seas; Or, The Marvelous and Exciting Adventures of Pierre Arronax, Conseil His Servant, and Ned Land a Canadian Harpooner.

A modern translation was produced in 1966 by Walter James Miller and published by Washington Square Press.[14] Many of Mercier's changes were addressed in the translator's preface, and most of Verne's text was restored.

Many of Mercier's errors were again corrected in a from-the-ground-up re-examination of the sources and an entirely new translation by Walter James Miller and Frederick Paul Walter, published in 1993 by Naval Institute Press in a "completely restored and annotated edition".[15] It was based on Walter's own 1991 public-domain translation, which is available from a number of sources, notably a recent edition with the title Twenty Thousand Leagues under the Seas (ISBN978-1-904808-28-2). In 2010 Walter released a fully revised, newly researched translation with the title 20,000 Leagues Under the Seas — part of an omnibus of five of his Verne translations titled Amazing Journeys: Five Visionary Classics and published by State University of New York Press.

In 1998 William Butcher issued a new, annotated translation from the French original, published by Oxford University Press, ISBN0-19-953927-8, with the title Twenty Thousand Leagues under the Seas. He includes detailed notes, an extensive bibliography, appendices and a wide-ranging introduction studying the novel from a literary perspective. In particular, his original research on the two manuscripts studies the radical changes to the plot and to the character of Nemo forced on Verne by the first publisher, Jules Hetzel.

The national origin of Captain Nemo was changed in most movie realizations; in nearly all picture-based works following the book Nemo was made into a European. However, he was represented as an Indian by Omar Sharif in the 1973 European miniseriesThe Mysterious Island. Nemo is also depicted as Indian in a silent film version of the story released in 1916 and later in both the graphic novel and the movie The League of Extraordinary Gentlemen. In Walt Disney's 20,000 Leagues Under the Sea (1954), a live-action Technicolor film version of the novel, Captain Nemo is a European, bitter because his wife and son were tortured to death by those in power in the fictional prison camp of Rura Penthe, in an effort to get Nemo to reveal his scientific secrets. This is Nemo's motivation for sinking warships in the film. Also, Nemo's submarine is confined to a set circular section of the Pacific Ocean, unlike the original Nautilus. He is played in this version by the British actor James Mason, with an English accent. No mention is made of any Indians in the film.

Finally, Nemo was depicted as Indian in a Soviet 3-episode TV film Captain Nemo (1975), which also includes some plot details from the "Mysterious Island", Jules Verne's sequel to the novel.

^Part 2, Chapter 7 "Accordingly, our speed was 25 miles (that is, twelve four–kilometer leagues) per hour. Needless to say, Ned Land had to give up his escape plans, much to his distress. Swept along at the rate of twelve to thirteen meters per second, he could hardly make use of the skiff. Leaving the Nautilus under these conditions"